The prior art jack primarily includes a hydraulic cylinder, a pump set, a lifting arm, a top disk, and supporting plates at two sides. Each of four ends at the bottom of the supporting plates is installed with a respective rolling wheel. However, such kind of jack has a dull and fixed outlook. Moreover, all the components are protruded. Thus, the components must be made to match with each other by the work of painting by baking or injection for beautifying. However, only the exposed portions are colored, and thus the all structure still appears a dull outlook without any attraction to users.